Good evening all,
My main question is this: Will the Alfa Spid RAK rotator fit in the top
section (section #3) of my Rohn HDBX-48 tower? Does the optional
mounting plate with short pipe stub have holes drilled to match the CDE
pattern? Has anyone done this?
I started this project back in August when I decided to replace my
ailing KT-34A with an antenna without traps, etc. I purchased an
Optibeam 10-3w and a T2x rotator. Apparently, I didn't do my research
very well and the Tailtwister, while being able to mount in the tower
did not have enough clearance to be able to rotate without modification
of the top section which I did not want to do. I ended up putting a new
Ham IV from Hy-gain - MFJ...(that's another story) on the new RP3
rotator plate, shimmed the 2" mast with 4 pieces of .031 steel shim
stock to match up with the TB-3 thrust bearing on the top plate and then
trammed the OB up on to the mast.
In my learning process, I have found that the Ham IV doesn't seem to
have the necessary torque to start the antenna rotating (moment/mass)
without some initial start-up protest (starts, slows down, and then
begins turning normally) - I had my XYL rotate the antenna while I was
up on the tower right at the rotor and I didn't like the sound of it.
Once rotating, it is fine. So far it has worked ok for about 2 weeks now
but I don't like the 6 degrees of play and the drama (element wagging,
etc) from the 10 elements when the rotator stops turning (before brake
application).
I think my best route at this point is to replace the H4 with the RAK
rotor along with a Green Heron controller to take advantage of the slow
ramp up and down of power which also should take some of the rotational
stress off of the tower....I am aware of the manufactures recommendation
on boom and element length for the HDBX-48.
Any thoughts or suggestions would be greatly appreciated. I have climbed
the tower 14 times now since I started this project and aside from sore
feet from the angle braces, it is getting harder for this 73 year old to
do tower work.
73, Dave - W3NP
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|